Antioxidant activity and quantification of phenols and flavonoids of Colombian plants used in urinary tract infections

Las plantas medicinales son de interés farmacéutico, debido a que tienen diferentes propiedades biológicas, entre las que se destaca, la actividad antioxidante y, de la cual, se conoce que existe una relación con la concentración de los compuestos fenólicos, por su capacidad de reducir los radicales libres. Es así, que se propuso evaluar la actividad antioxidante y la cuantificación de fenoles y flavonoides totales, de 11 extractos etanólicos de plantas, empleadas en la medicina tradicional, para el tratamiento de infecciones urinarias (IU). Se evaluó la actividad antioxidante, por los métodos de DPPH y FRAP y se cuantificó el contenido fenólico y de flavonoides, por el método Folin-Ciocalteu y tricloruro de aluminio, respectivamente. Se encontró que, de los 11 extractos evaluados, los que presentaron el mayor contenido de estos metabolitos y de potencial antioxidante fueron: Uncaria tomentosa, Sedum praealtum y Kohleria hirsuta. Este trabajo permitió contribuir al conocimiento fitoquímico y antioxidante de plantas, usadas para tratar IU y se sugiere que U. tomentosa, S. praealtum y K. hirsuta sean objeto de futuros estudios biodirigidos, así como la evaluación de otras actividades biológicas.Medicinal plants are of pharmaceutical interest because they possess different biological properties, among which their antioxidant activity stands out, and therefore it is known that there is a relationship with the concentration of phenolic compounds due to their ability to reduce free radicals. Therefore, it was proposed to evaluate the antioxidant activity and the quantification of phenols and flavonoids of 11 ethanolic extracts of plants used in traditional medicine for the treatment of urinary infections (UI). The antioxidant activity was evaluated by the DPPH and FRAP methods and the phenolic and flavonoid content was quantified by the Folin-Ciocalteu and aluminum trichloride method, respectively. It was found that of the 11 extracts evaluated, those with the highest content of these metabolites and antioxidant potential were three: Uncaria tomentosa, Sedum praealtum and Kohleria hirsuta. This work made it possible to contribute to the phytochemical and antioxidant knowledge of the plants used for the treatment of UI and it is suggested that U. tomentosa, S. praealtum and K. hirsuta be the object of future bio-directed studies, as well as the evaluation of other activities biologicalIncluye referencias bibliográfica

Microwave extraction of champa (Campomanesia lineatifolia Ruiz & Pav.) fruit: alternative to obtain natural antioxidants

Champa (Campomanesia lineatifolia Ruiz & Pav.) is a fruit tree that belongs to Myrtaceae family and is native from the Amazon. Champa fruit has special organoleptic characteristics like its flavor and is an important source of phenolic compounds useful in food industry. Currently, the postharvest process of champa fruit needs to be improved due to fruit losses, which had achieved a 97%. In this sense, the aim of this research was to evaluate microwave extraction to obtain extracts enriched in phenolic compounds from champa fruit. The evaluated variables were as follows: microwave power (100-200W), extraction time (1-2min) and solvent (water, ethanol-water 70:30 and ethanol-water 96:4), respectively. Results showed that the best condition to obtain phenolic extracts involved the use of water as solvent, 100W of power and 2min of extraction time. Given these concerns, was possible to obtain a yield higher than 60%. The obtained extracts had achieved a maximum antioxidant activity of 11.36 and 31.44 mg of Trolox.g-1 of dry pulp through DPPH and FRAP methods. In fact, the higher phenolic concentration (3450.73 μg Gallic acid. g-1 of dry pulp) was obtained with a 200 W of microwave power, water as solvent and 1 min of extraction time. These results suggest that champa fruit is a source of phenolic extracts with antioxidant activity, which are useful for agroindustry sector, especially as natural additives to extend the shelf life of different products

Antiquorum and Antibiofilm Activities of <i>Piper bogotense</i> C. DC. against <i>Pseudomonas aeruginosa</i> and Identification of Bioactive Compounds

The present study describes the anti-biofilm and quorum sensing (QS) inhibitory potential of extracts and chemical constituents from Piper bogotense. Antibiofilm potential was determined through crystal violet assay against Pseudomonas aeruginosa, while QS inhibition efficacy was determined through violacein inhibition assay using Chromobacterium violaceum as a bacterial model. Additionally, this study reports the effects of the chemical constituents isolated in P. bogotense against various virulent factors associated with QS, such as the percentage decrease in pyocyanin, elastase, and protease production. The chemical study led to the isolation and identification of two prenylated benzoic acids (1 and 2) and a prenylated hydroquinone 3, of which compounds 1 and 2 are reported for the first time for P. bogotense. The ethanolic extract and the DCM fraction from P. bogotense stand out for reducing violacein production in C. violaceum, as well as the biofilm formation in P. aeruginosa. Compounds 2 and 3 stand out for having the lowest violacein production (43.8% and 68.3%), as well as the lowest production of virulence factors such as elastase (60.2% and 51.4%) and pyocyanin (39.7% and 33.2%). These results demonstrate the potential of P. bogotense components to be used as an alternative control against multidrug-resistant P. aeruginosa